Interfacial properties of penta-graphene-metal contacts

Novel properties of penta-graphene (PG) have stimulated great interest in exploring its potential for device applications. Here, we systematically study the interfacial properties of the heterojunctions constructed by stacking PG on several metal substrates (Ag, Al, Au, Cr, Cu, Pd, and Ti), which are commonly used in field-effect transistors. We consider PG as the channel material because of its semiconducting feature, while treating the metal surfaces as the electrodes. Based on first principles calculations, we show that PG preserves its pentagonal feature with some small distortions when deposited on the metal substrates but undergoes metallization due to the chemical bonding between PG and the metal surfaces. We evaluate the device potential of these PG-metal contacts by studying their tunneling barriers, orbital overlaps, and Schottky barriers. We find that PG forms an n-type Schottky barrier when in contact with Al, Cu, and Ti, but forms a p-type Schottky barrier when supported on Ag, Au, Cr, and Pd. Our study sheds light on the design and fabrication of PG-based electronic devices. Published under license by AIP Publishing.